For some time leaf springs have been used in automotive engineering, which however are nowadays made from glass-fiber-reinforced plastic in order to be able to fulfill weight-saving demands. Such GFR (Glass Fiber Reinforced) transverse leaf springs are also intended to perform wheel-guiding tasks and to replace three previously essential components of a vehicle axle. Those components are a so-termed body spring, a stabilizer and a transverse control arm.
To perform the wheel-guiding functions transverse forces have to be introduced into the GFR transverse leaf spring and supported by means of central mountings in the area of the vehicle body. The central mountings always represent a compromise between the mobility of the GFR transverse leaf spring and the transverse force to be supported in each case. It is true that the GFR material used in each case for making a GFR transverse spring is light and correspondingly innovative, but as regards the input and output of the force, appropriate design measures are required.
This results from the fact that depending on the axle kinematics existing in each case, differently sized lateral movements of the GFR transverse leaf spring in the central mountings can occur, which are superimposed with rotation that in turn takes place during jouncing or rebound processes of the GFR transverse leaf spring. In the area of the mounting points of the GFR transverse leaf spring, a combination of these movements produces bearing forces whose result is that a mounting design suitable for a particular axle kinematic is completely unusable with a different axle kinematic and causes premature impairment of the function of the GFR transverse leaf spring.
From DE 10 2009 028 900 A1 a bearing mechanism for a transverse leaf spring is known, which comprises a mounting outer shell device and insertion devices at least partially surrounded by the mounting outer shell device, each having sheet elements of different rigidity. In the assembled condition the insertion devices are in each case arranged between the mounting outer shell device and the transverse leaf spring. Sheet elements with higher rigidity are in each case positioned between the transverse leaf spring and sheet elements with lower rigidity. The sheet elements with higher rigidity are in the form of convex half-shells between end areas orientated in the axial direction of the transverse leaf spring. The end areas of the more rigid sheet members have portions curved concavely relative to the surface of the transverse leaf spring, whose free ends are directed away from the surface of the transverse leaf spring. The sheet elements formed with lower rigidity and the sheet elements adjacent to the transverse leaf spring partially surround the less rigid sheet elements with their free ends.
The mounting design of the bearing mechanism is symmetrical, whereby when the transverse leaf spring is in its fitted position a cross-sectional plane of the transverse leaf spring that extends essentially in the vertical and longitudinal directions of the vehicle in the area of the bearing mechanism can pivot, during jouncing and rebounds of the transverse leaf spring, about a rotational axis extending essentially in the longitudinal direction of the vehicle, which, without producing undesired constraining forces in the area of the transverse leaf spring, must as a result of the design be located in the area of the neutral fiber of the transverse leaf spring.